The present invention relates to a new and distinct cultivar of Hibiscus, known commonly as Rose of Sharon, and considered an ornamental shrub or small tree for use in garden and landscape. The new cultivar is of the family Malvaceae, known botanically as Hibiscus syriacus, and will be referred to hereinafter by the cultivar name ‘CARPA’.
‘CARPA’ was discovered in 2000 as a naturally occurring branch mutation of the parent, an individual Hibiscus syriacus ‘Ardens’ (unpatented). Discovery occurred in a growing crop of ‘Ardens’ at the inventor's nursery in Strathroy, Ontario, Canada. The inventor selected ‘CARPA’ based on the criteria of bold leaf variegation, flower traits including color and sterility.
The distinguishing traits of ‘CARPA’ are strongly conspicuous leaf variegation, with yellow color fading to white as foliage matures, double flowers that open completely, and are sterile. The closest comparison plants are Hibiscus ‘Meehanii’ (unpatented) and Hibiscus ‘America Irene Scott’ (U.S. Plant Pat. No. 20,579). Comparison plant ‘Meehanii’ produces flower buds that are burgundy in color, and rarely open completely, while the comparison plant ‘America Irene Scott’ exhibits weak foliage variegation, and produces flowers that are pale bluish-pink in color. ‘CARPA’ is distinguishable from Hibiscus ‘Meehanii’ by consistent flowering of blossoms that open completely, and is distinguishable from ‘American Irene Scott’ by strongly conspicuous leaf variegation, flower color, and dramatic color combination of foliage and flower.
‘CARPA’ exhibits robust upright growth habit, medium branch density, semi-upright branch attitude, brown stems, boldly variegated foliage ranging from mid-green to yellow on young leaves, with the yellow color fading to white as leaves mature. Showy, ruffled, double flowers are of the violet color group, with dark contrasting centers of the red-purple color group. The flower of ‘CARPA’ is sterile and opens completely. Branching is compact in young plants, opening at maturity. Plants of ‘CARPA’ are 1.8 meter in height and 1.2 meter in width at maturity.
Suitable cultivation includes full sun, well-draining humus-rich, fertile soil, given regular water during growing periods and then reduced to minimal water. Hardiness is USDA Zone 6. ‘CARPA’ is recommended for use as a garden specimen, landscape planting, and as a container plant. In the garden ‘CARPA’ can be espaliered, pruned into a hedge, or easily pruned into a single trunk tree. ‘CARPA’ is winter deciduous and, depending on placement, can be drought tolerant.
‘CARPA’ was first asexually propagated in Strathroy, Ontario at the inventor's nursery. The inventor conducted asexual propagation in 2004 using the method of softwood cuttings. Since that time, under careful observation, the distinguishing characteristics of ‘CARPA’ have been determined fixed, stable, uniform, and have been shown to reproduce true to type in successive generations of asexual propagation.
The inventor filed an application for Canadian Plant Breeders Rights for ‘CARPA’, application number 09-6661, application date Jun. 9, 2009. The application was granted on Feb. 24, 2012, grant number 4283.
No sales or offers for sale have been made anywhere in the world at the time of filing this plant patent application.